Always stick around until the credits are over when you're watching something from Marvel!
Frank Castle, aka the Punisher, was introduced in Season 2 of Daredevil. He's a military veteran who turns to brutal, murderous vigilantism after his family is killed by the mob. He's on a mission to wipe crime off the face of the Earth. He's like Travis Bickle on steroids.
The teaser sets a dark tone for the series. It features Castle pounding concrete with a sledgehammer and gutturally screaming. In voiceover, he reflects on the memories of all the terrible things he's done and either compares himself to the Devil or says he sold his soul to the Devil or says that the past is the Devil. It's a little unclear. Whatever it is, he's coming to collect.
Marvel's The Defenders is available to stream now. Marvel's The Punisher is coming to Netflix later this year.